According to the sum of the EIA and Baker Hughes International Rig Counts, during April 2012, there were approximately 3,500 rotary drilling rigs worldwide, wherein analysis of the EIA data suggests that each rotary drilling rig on average drills 2 wells per month, which further suggests that 7,000 wells may be drilled by rotary drilling rigs worldwide each month. EIA data for the United States also suggests that the average depth of a well in 2008 was around 6,000-ft, wherein as an artisan of the art of drilling hydrocarbon wells, the present inventor suggests that, based on the time necessary to bore and remove rock from a borehole, drilling two wells per month of around 6,000-ft in depth suggests that a large percentage of those 7,000 wells per month are completed with 4½ to 7 inch liners at the lower end of 9⅝ inch casings with 2⅜″ to 4½″ production tubing.
Furthermore, while the numbers of wells drilled in the United States may have peaked at 8,000 U.S. wells per month around 1982, and dropped as low as 2,000 U.S. wells per month between 1986 and 1996, the average since 1973 is around 3,500 U.S. wells per month. Hence, using the same Rotary Drill Rig Count logic described above, a present average of 7,000 wells per month worldwide, or 84,000 wells per year worldwide, may be representative of an overall worldwide average since 1973, wherein the stock of wells requiring abandonment must also be around 7,000 wells per month worldwide or 84,000 wells per year worldwide, lest the stock of wells to be abandoned increases exponentially. Hence, since abandonment of a well represents an investment without return on capital, the propensity is to postpone abandonment; and hence, on an average, the number of wells requiring abandonment in the future is likely to be more.
Accordingly, the significance of a downhole tool's diameter relative to then number of wells, using small diameter tubing and the number of wells requiring abandonment worldwide, should not be discounted, since the well abandonment market each year will be measured in billions of dollars and pounds sterling worldwide.
It is equally important, from the view of supplying tooling for abandoning said wells, that the diameter of the tooling be kept as small as possible, while having the ability to expand as large as possible to accommodate the differences in tubing sizes worldwide, wherein maintaining an inventory of off-the-shelf tooling suited for the majority of well sizes may be exceptionally costly, unless a minimum of diameter changes is maintained across downhole tools to minimise the stock of tool sizes, and wherein the physical restrictions of working within a smaller diameter limits their functionality.
The present invention purposely provides small diameter tools with significant expansion capabilities to provide the most economical solution for worldwide abandoning, suspending and side-tracking of wells.
Constructing a subterranean well, for producing substantially water, e.g. from solution mined or water cut hydrocarbon wells, or producing substantially hydrocarbons, requires capital investment with an expectation of a return on capital, repaid over the life of the well, followed by the permanent abandonment of all or part of the well, typically referred to as suspension, to delay further cost, once storage or producing zones have reached their economic life or well structural integrity becomes an issue. For the hydrocarbon extraction industry, the producing life of a well is, typically, designed for five (5) to twenty (20) years of production. However, conventional practice is primarily to extend well life as long as possible, even after exceeding its original design life, and, despite any marginal economic losses incurred, to push the cost of final abandonment into the future. For the underground storage industry, wells may be designed for a fifty year life span, but, over time, storage wells may encounter integrity issues that require intervention, maintenance or abandonment.
Embodiments of the present invention can be usable to delay abandonment by using well barrier element placement to intervene in or to maintain a well's structural integrity and to allow additional marginal production from other zones after, e.g., suspending a watered-out reservoir formation, or storage operations, until final cessation of production or storage operations, when the proposed benchmarking, development, testing and improvement of new technology may take place. Various embodiments of the present invention can be further usable to permanently abandon all or a part of produced subterranean or underground storage wells, during the benchmarking, development, testing and improvement of new technology.
As the cost of placing acceptable abandonment barriers to permanently isolate subterranean pressurized liquids and gases comprises an investment without a return on capital, the financially minded continue to seek to reduce the net present cost of abandonment by either delaying it, through marginal production enhancement, or by minimising expenses associated with abandoning the lower portion of a well, sometimes referred to as suspension until final abandonment of a well.
Methods of the present invention can be usable with rig-less intervention operations for minimizing the cost of marginal production enhancement and for abandoning a portion of a well, until a final abandonment campaign can be used to further minimize costs, by using rig-less method embodiments to benchmark, develop, test and improve new technology in a risk-controlled environment and over the life of such an abandonment campaign.
Well abandonment represents actions taken to permanently isolate subterranean pressurized fluids from surface and/or other lower pressured exposed permeable zones, e.g. water tables, for various portions of a well where re-entry is not required, and wherein the portions, being selectively used and/or abandoned, require permanent fluid isolation at depths specified by pressures within the strata and by the pressure bearing ability of the overlying strata to isolate lower strata fluid pressures from the surface or other upper permeable zones. Subterranean pressurized permeable zones, comprising strata formations accessed by a well with a possibility of fluid movement when a pressure differential exists, generally, must be isolated to prevent pollution of other subterranean horizons, such as water tables, or surface and ocean environments.
Various embodiments of the present invention are usable within a pressure controlled working envelope, using coiled strings, lubricators, grease heads or other pressure control equipment engaged to the upper end of a wellhead and valve tree to intervene within the passageways and annuli of a subterranean well extending downward from the wellhead to test and measure permanent isolation of subterranean pressurized fluids, which can be accessed by the passageways without the risk and cost of placing dense kill weight fluids in the well and breaking through surface pressure barriers, thus exposing personnel and the environment to a higher potential for uncontrolled fluid flow, if the dense fluid column killing subterranean pressures is lost through, for example, subterranean fractures.
Performing well intervention and abandonment operations within a pressure contained environment is required for rig-less operations in a subsea environment where risers and lubricators must be engaged to the upper end of a subsea valve tree to remove plugs for accessing the innermost well bore. However, access to annuli within a subsea well is limited, with most wells opening the innermost annulus to the production stream during initial thermal expansion, after which subsea annuli are closed. Many subsea configurations also provide fluid access to the innermost annulus through a manifold placed on the subsea valve tree, which may be engaged with the supporting conduit pipelines, such as a methanol line. The methods of the present invention can be usable from a boat and lubricator arrangements within a pressure controlled environment, e.g. a subsea lubricator and BOP, to rig-lessly test and measure access and abandonment of a well without the need for a riser to sea-level.
Permanent abandonment, generally, is considered to be the placement of a series of permanent bathers, often referred to as plugging and abandoning, in all or part of a well with the intention of never using or re-entering the abandoned portion. Permanent well barriers are, generally, considered well barrier envelopes comprising a series of well barrier elements that, individually or in combination, create an encompassing seal that has the permanent or eternal characteristic of isolating deeper subterranean pressures from polluting shallower formations, e.g. ground water permeable zones, and/or above ground or ocean environments. Various publications, including Oil and Gas UK Issue 9, January 2009 Guidelines for Suspension and Abandonment of Wells, NORSOK Standard D-010 Rev 3, August 2004 and the Well Plugging Primer by the Texas Railroad Commission, incorporated herein in their entirety by reference, define conventional best practice for permanent abandonment of a well and the associated acceptable well barrier elements used to form a plurality of pressure bearing envelops for resisting subterranean pressurized liquids and gasses over geologic time, wherein Article 3 of the Texas Railroad Commission 1919 S.B. 350 rules recites “dry or abandoned wells be plugged in such a way as to confine oil, gas, and water in the strata in which they are found and prevent them from escaping into other strata.”
Presently, there are no known conventionally proven comprehensive systems for abandoning wells that provide concentric cementation and cement bonding, other than the systems of the present inventor or systems requiring the use of an over-specified and expensive drilling rig. Unlike any of the existing systems, the present invention comprises a method for first measuring and using conventional apparatuses to rig-lessly abandon wells and to provide a benchmark, after which new rig-less technologies or methods and apparatuses of the cited applications of the present inventor and those of the present invention, may be developed, tested and improved during the rig-less suspension and/or abandonment of onshore and/or offshore, surface and/or subsea, substantially hydrocarbon or substantially water wells, using published conventional best practices for placement of industry acceptable cement-like permanent abandonment well barrier elements.
With an estimated 84,000 wells being drilled every year worldwide, rig-less abandonment is a critical factor in allocating the industries resources to further discovery and production enhancement, instead of abandonment, which is further explained within application publication GB2487274 of the present inventor, which is included herein in its entirety by reference for supportive reasoning.
A need exists for a set of rig-less abandonment tools that can be applicable across a larger percentage of the worldwide wells reaching the end of their productive life, which can minimise the number of off-the-shelf variations of the tool set, allowing the effective disposal of aging well components downhole and providing concentric cementation and cement bond logging before and after said cementation. The wells being abandoned in bulk may also be used for the benchmarking, developing, testing and improving of new technology that can be usable to verify said tool set and other downhole technologies, usable to facilitate a market where the reduction of well abandonment liability allows larger, higher-overhead operating companies to sell marginal well assets to smaller, lower-overhead operating companies by lowering the risk of a residual abandonment liability and including the application of new technologies to increase recoverable reserves, thus preventing usable hydrocarbons from being left within the strata by the lack of sufficient technological innovation.
The embodiments of the present invention provides significant improvements to the oil and gas industry by providing methods and apparatus for a cable conveyable tool string, which can be usable for providing concentric cementing and cement bond logging, before and after cementation, where none has previously existed.
Methods of the present invention is the destruction and permanent well barrier element placement within the lower portion of a well, at the lowest possible cost, by providing disposable cement bond logging apparatus and methods and to provide space above said destruction for benchmarking, developing, testing and improving new technology. Embodiments of the present invention include low cost, simple and robust methods usable to test apparatus and methods.
Various embodiments of the present invention can be usable to measure formation of an enlarged passageway, including the cutting and/or displacing of well conduits, equipment for compression or compaction of installed well conduits and equipment to form or enlarge passageways for placement of a permanent well barrier element. Other embodiments can be used for testing expandable casings, expandable seals or swellable materials within bores and annuli of a well to form pressure bearing passageways that can be usable to form a space after cutting or displacing conduits to place, e.g., logging equipment, to determine any necessary remedial action within a bore or annuli of a well. Still other embodiments can include placing depth sensors in protective housing to measure the formation of space and associated fluid isolation for determining efficiency benchmarks. Such methods can be usable for benchmarking, development, testing and improvement of new rig-less technology during final abandonment of subterranean portions of a well, without incurring unacceptable risk of working above a well barrier that is not tested in direction of flow, while maintaining low cost operations.
In addition, embodiments within the scope of the present disclosure provide a tool string that can be usable across a spectrum of conduit sizes, for example, casing or similar conduits ranging from an outer diameter of 2⅜ inches to 36 inches, for use in wells worldwide.
Embodiments of the present invention provide significant improvements to methods described in UK Patent GB2471760, entitled “Apparatus And Methods Subterranean Downhole Cutting, Displacement And Sealing Operations Using Cable Conveyance” filed Jul. 5, 2010, and UK Patent Application GB1111482.4 published as GB2484166, entitled “Cable Compatible Rig-Less Operatable Annuli Engagable System For Using And Abandoning A Subterranean Well,” both of which were filed by the present inventor and each of which is incorporated herein in its entirety by reference. In addition. embodiments of the present invention can be usable with rigs or conventional rig-less arrangements, such as those described in U.S. Pat. No. 7,921,918B2, published the 12th of Apr. 2011, and incorporated herein in its entirety by reference to provide reference,
Embodiments of the present invention can be usable to provide concentric cementing and acoustic monitoring after said cementing in an existing bore during any of abandonment, suspension and side-tracking operations, which provides a vast improvement to methods relating primarily or solely to detecting and locating fluid ingress in a well bore, particularly methods using acoustic sensing of individual acoustic signals from a plurality locations along the well bore for analysing them to determine the likelihood of fluid ingress, and using such technology as fibre optic cable or microphones placed along the well bore for detection,
Embodiments of the present invention can be usable to communicate through slickline for providing improved detection of leaks, breaches and/or information regarding the characteristics of a cement annulus between a casing in a borehole and the surrounding earth formations in a slickline cement bond logging operation, including the use of acoustic logging tools that produce a pure signal downhole when captured in memory downhole using a time amplitude matrix that stores data points for producing a cement bond log at the well surface
Existing methods and systems generally pertain to wireline and coiled string deployment that should not be left in situ, and/or which use the limited force of conventional tools that are unable to, for example, pass passageway restrictions, crush compressible well components or orient explosive devices axially, because components used with these existing methods and systems may be propelled out of the well or otherwise damaged, or stuck within the wellbore, if operated with the same hydraulic and/or explosive forces usable with the embodiments of the present invention. In addition, existing methods and systems relating to wireline conveyable expandable axial displacement spring slips lack many features of the present invention, including the use of devices that can be fashioned to be moveable or to achieve the expanded diameter to collapsed diameter ratio necessary for passage through, e.g., a collapsed conduit bore's walls.
Further, although conventional methods include wireline dumping of cement upon, for example, a restriction or bridge plug, these conventional methods do not include the passage of a downhole device past a restriction, and with regard to methods using deformable members in a downhole device, such methods are not usable in situations encumbered by the deformity of well conduits where it is necessary to pilot such devices into, e.g., a damaged or debris filled well bore.
The majority of the existing methods and systems for passage through a wellbore presume the use of a circular well bore, without significant restriction to deployment of a downhole device, for example, the deployment of a downhole device through a collapsed casing. Generally, conventional methods do not include a practicable cost effective means of deploying or urging the deployment of a downhole device through, for example, the debris of a collapsed casing section, and including the orienting of the collapsed tubing or casing axially downward to either cut or expand a failed well conduit. In addition, existing methods and systems lack interoperability between tools in the deployment string that are necessary to pilot a tool string and to traverse through intermediate debris and/or damage to a lower end of a well bore, without the removal of said debris through the act of well bore circulation.
While various conventional methods and systems for passage through a wellbore exist, it is not known in the industry how said conventional methods and systems may be practicably deployed to provide repeated access and to provide passage to a well's lower end. Embodiments of the present system meet the needs for repeated access and passage to a well's lower end by providing the piloting and selective orientation of a tool string, relative to substantially differing circumferences along an erratic axis of a contiguous passageway's walls, which have been formed by deformation or damage along and/or debris within or on the dissimilar passageway walls.
Other industry needs include a need for apparatus and methods usable for the concentric placement of cement and cement bond logging thereof within, for example, wells that for various reasons may be damaged or otherwise filled with debris, wherein wellbore wall deformation and friction reducing methods and apparatus, that are conventionally usable with coiled tubing and/or drill strings, are not conventionally available to wireline,
A need exists for apparatus and methods usable for economically establishing reference benchmark data for the use of new and conventional apparatus, comprising both mechanical and fluid apparatus, which can be usable with a coiled string and measurable with conventional logging measurement devices and shock absorbing housing methods, and including apparatus and methods to provide a basis for developing and improving unconventional abandonment, suspension and side-tracking of a plurality of passageways in a well without using a drilling rig, or to substantially reduce the time spent by a drilling rig during such operations.
A need exists for apparatus and methods usable with new technology that may be benchmarked, developed, tested and improved, such as conventional apparatuses used in unconventional ways, unconventional methods and apparatuses used in unspecified ways, and other unconventional methods and apparatuses.
A need exists for rig-less methods and systems usable with conventional and new apparatuses to eliminate the need to remove installed conduits, thus allowing measurement in all circumstances, including where the installed well equipment and any associated scale or naturally occurring radioactive material are left downhole, thus providing an environment for conventional and new technological benchmarking, development, testing and improvement while meeting published industry best rig-less abandonment practices during formation of permanent well bather elements and indefinite abandoned well integrity
A need exists for methods usable to reduce or eliminate all risks associated with the benchmarking, development, testing and improvement of rig-less procedures and tools of a conventional and unconventional nature.
A need exists for methods and apparatus usable to provide a means for a concentrically cemented and cement bond logged isolation within a wellbore and for making it safer from fluid ingress, comprising, for example, the use of rheological controllable fluid members, logging tool members, expandable members, swellable members, placeable conduit members, motorized members, boring members, tractor members, conduit shredding members and milling members, or any new technology, or any other members that may be benchmarked, developed, tested and improved.
A need exists for apparatus and methods that may be safely used and tested within a geological space, confirmed by use of concentric cement placement and cement bond logging methods to confirm the placement of well barrier elements for isolating at least a lower portion of the wellbore. In addition, a need exists for methods usable to benchmark, develop, test and improve access to subterranean boreholes, conduits, annuli and producible zones of a well to perform rig-less well abandonment, thus providing the basis and confidence for industry to benchmark, develop, test and improve various in use methods and apparatuses, in a new manner.
A need exits for apparatus and methods usable to meet published industry best practice for final rig-less well abandonment of wells using conventional off-the-shelf technology, thus saving the cost of using a drilling specification rig, while providing an environment for further saving of costs by incrementally benchmarking, developing, testing and improving various procedures and tooling.
A need exists for apparatus and methods usable to increase the number of wells where lower cost rig-less slickline operations can be usable to place permanent well barrier elements, like cement, where the use of conventional apparatuses and methods would require use of extremely expensive and over specified drilling rigs and equipment to perform remedial work on wells.
A need exists for apparatus and methods usable and combinable with conventional fluid and mechanical apparatus for placing well barrier elements to perform benchmarking, development, testing and improvement of conventional and newly developed rig-less operable methods and apparatus, by testing the isolation of subterranean pressures to provide a safer, lower risk and lower cost testing environment.
Various embodiments also provide very small diameter tools deployable through small diameter tubing and usable to operate within substantially larger diameter surrounding bores within abandonment, suspension and side-tracking operations that cannot be provided by prior art or conventional tooling.
Embodiments of the present invention are usable to address these and other needs.